Field of the Invention
The present invention relates to an organic light emitting display device, and to an align mark necessary for a scribing process which is performed for obtaining a plurality of unit panels from a mother substrate.
Discussion of the Related Art
Organic light emitting display devices are display devices that self-emit light, and have a structure where an organic emission layer is formed between a cathode and an anode. Due to this structure, an electron supplied from the cathode and a hole supplied from the anode are injected into the organic emission layer to generate an exciton, and the generated exciton shifts from an excited state to a ground state to emit light.
The organic light emitting display devices are obtained through a process where a plurality of unit panels (U/P) are provided on a mother substrate and then are cut through a scribing process. Hereinafter, a related art organic light emitting display device will be described with reference to FIGS. 1A to 1C.
FIGS. 1A to 1C are schematic illustrations of a process of manufacturing a related art organic light emitting display device.
First, as shown in FIG. 1A, a plurality of unit panels U/P are provided on a mother substrate 1a. In the drawings, only two unit panels U/P are illustrated for convenience.
First alignment marks 2 for a first scribing process are formed at the corners of the mother substrate 1a, and second alignment marks 3 for a second scribing process are formed at the corners of each of the plurality of unit panels U/P.
Subsequently, as shown in FIG. 1B, a first scribing process is performed by using the first alignment marks 2 to obtain a. plurality of unit panels U/P.
In this case, a test area T/A is provided in each of the plurality of unit panels U/P, and a test process is performed for each of the unit panels U/P.
Subsequently, as shown in FIG. 1C, a second scribing process is performed by using the second alignment marks 3 formed in each of the unit panels U/P, and the test area T/A is removed from the each of the unit panels U/P.
As described above, the related art organic light emitting display device is manufactured using the first scribing process based on the first alignment marks 2 and the second scribing process based on the second alignment marks 3. However, the second alignment marks 3 are not easily and clearly observable during the second scribing process. Thus, the second scribing process is not performed smoothly.
In FIG. 1C, the enlarged portion corresponds to a cross-sectional surface of an area where a second alignment mark 3 is formed. In this case, each of the second alignment marks 3 are formed on a substrate 1, an encapsulation layer 5 for preventing penetration of water is formed on each of the second alignment marks 3, and an encapsulation substrate 7 is provided on the encapsulation layer 5.
As described above, in the related art, since the encapsulation layer 5 is formed on the second alignment marks 3, the second alignment marks 3 are not easily observable, and the second scribing process for removing the test area T/A from each of the unit panels U/P is not performed easily or smoothly.